We propose to develop, implement, and validate use of a computerized control system for MR-monitored thermal therapies (interstitial laser thermal therapy and cryotherapy) that is to be attached to our 0.5T open configuration interventional MR scanner. The system will utilize 3D MRI information, providing audible and visual prior warning signals and an alarm signal at the therapy endpoint.
We aim to directly answer the cancer treatment clinical need for accurate 3D spatial-temporal monitoring and control of tumor thermal therapies in heterogeneous tissue, currently beyond human capability, to guarantee patient safety while optimizing therapy effectiveness. Our proposed system will provide recognizable prior warning signals before the endpoint is reached, and an alarm signal at the instance when the thermal therapy endpoint occurs, as the thermal exposure level or therapy boundary meets or exceeds pre-defined 3D boundaries or safety limits. Specifically, our project consists of: (1) the integration of specially configured computer hardware into our interventional MR scanner electronics; (2) the development of a software package and user-interface for 3D monitoring and control of a thermal ablation therapy based on a physician-specified therapy volume boundary and exposure limit; (3) initial off-line system testing using gel phantoms and posttreatment human patient MRI data; and, (4) fully on-line real-time validation testing during tumor thermal therapies on our interventional MR scanner. Software will be developed or integrated into the system to provide state-of-the-art capability for monitoring and predicting evolving therapy margins and thermal exposure. In Software Module One, a monitoring and control system will be developed based on 3D optical flow, previously demonstrated as clinically useful in our hospital. In Software Module Two, a parallel predictive pathway will be created combining existing fast 3D data segmentation and heat conduction modeling software. In Trial Phase One, off-line (not in real-time) gel and 'virtual' patient tests will be performed and control case data acquired. Later, in Trial Phase Two, real-time validation trials will take place during clinical therapy cases, to study the accuracy, usefulness and timeliness of the system results when executing on the specific computer hardware chosen for implementation.
